1. Field of the Invention
The present invention relates to an overhead scanner, an image obtaining method, and a computer-readable recording medium.
2. Description of the Related Art
Conventional overhead scanners that improve operability have been developed.
In order to provide excellent operability when reading documents and to obtain high-definition images, there is an overhead scanner that determines that a read operation is started on the basis of velocity vectors obtained by extracting feature points (see Japanese Patent Application Laid-open No. 2011-254366).
Moreover, there is a scanner that, when a scanned image is formed by correcting a frame of a moving image captured by a high-speed area sensor, successively monitors a projected light pattern reflected from an object, detects a change within an area region by extracting a difference, and detects a change in an object by comparing the detection results (see Japanese Patent Application Laid-open No. 2003-244531).
However, there is a problem with conventional scanners that they easily produce a false detection, i.e., the detection of a movement other than a predetermined movement, and therefore the accuracy with which a predetermined movement is correctly detected is low.
The present invention is achieved in view of the above and has an object to provide an overhead scanner, an image obtaining method, and a computer-readable recording medium capable of preventing a false detection and detecting the start of a read operation with high accuracy.